Apparatus for vulcanizing elastomeric hose

ABSTRACT

An elastomeric hose is encased in a lead sheath and continuously wound in a coil over a drum rotating about a vertical axis, heated to vulcanizing temperature while thereon and leaves the drum in the cured state. The cured hose leaves the drum continuously at a level lower than that at which it enters whereby the lead covered coil drops one pitch with each revolution of the drum such that the position of the hose coil on the drum remains substantially fixed.

Unlted States Patent 1151 3,690,796 Borsvold [4 1 Sept. 12, 1972 1APPARATUS FOR VULCANIZING R ferences Cited ELASTOMERIC HOSE UNITEDSTATES PATENTS [72] Inventor: Herbert H. Borsvold, Akron, Ohio 3,255,2846/1966 Meislohn ..264/ 166 X 3,479,419 11/1969 Hochhauser ..264/347 X[73] Assgnee' I, 3' Sgf 3,154,442 10/1964 Nye etal ..263/3 x 3,015,427l/l962 Kessler ..18/12 TT ux [22] Filed: Aug. 21, 1970 PrimaryExaminer-Robert L. Spicer, Jr. [21] 65,776 Attorney-W. A. Shira, Jr. andJoseph J. Januszkiewicz [52] U.S. Cl. ..425/90, 263/3, 263/32,

264/166, 264/347, 425/113, 425/289, [57] ABSTRACT 425/383 An elastomerichose is encased in a lead sheath and [51] 1111. C1 ..F27b 7/20, F27b9/28,B29h 7/14 continuously wound in a coil e a um rotating 53 Field fSearch 1 12 TM, 21 2 T3, 12 about a vertical axis, heated to vulcanizingtempera- TT, 18/4 B, 4 P, 4 S, 135.13.R, 13 J; 164/86, 270, 275, 276;29/527, 2, 424; 264/166, 347; 263/3, 32; 425/90, 383, 289, 113

ture while thereon and leaves the drum in the cured state. The curedhose leaves the drum continuously at a level lower than that at which itenters whereby the lead covered coil drops one pitch with eachrevolution of the drum such that the position of the hose coil on thedrum remains substantially fixed.

4 Claims, 2 Drawing Figures Patented Sept. 12, 1972 w w ms QR 0 H T R mR E H BACKGROUND OF THE INVENTION In the manufacture of elastomerichose, one method for curing mandrel built hose of diameters generallyless than two inches is that of extruding a lead sheath over the hoseand placing it into an oven for vulcanizing. In this method, the hose issandwiched radially in compression between the lead sheath and themandrel during the vulcanizing operation.

Heretofore, this method of curing elastomeric hose has been appliedcommercially in either of two forms. In one form, designated lengths ofthe lead covered hose have been cut andplaced in a linear configurationin an oven of sufficient length and size to accept a desired number ofhose lengths in one charge. In this form or manner of curing, the numberof hose lengths that can be cured in one charge or cycle is obviouslylimited by the size of the oven. Thus, where it is desired to cure alarge quantity of hose sections at one time, a large and costly oven isrequired or, in the alternative, a plurality of ovens of lesser size inwhich case the initial cost of the ovens is often prohibited.

The other manner commonly used for curing hose which has been coveredwith a lead sheath incorporates winding a desired length of lead coveredhose to be cured on a drum or spool and then transporting the spool oflead covered hose into an oven for curing.

In general, the technique of curing elastomeric hose wherein the hose isencased in lead prior to and during the curing cycle, has involvedcumbersome handling steps which require expensive equipment for handlingand which further prevent rapid curing of the hose and thus result in alimited production rate. Moreover, a large quantity of lead is requiredfor this batch type curing. It has thus been desirable to find anefficient method for continuous rapid curing of elastomeric hose whileencased in a lead sheath without requiring the hose to be handled inseparate lengths while covered with lead and retain the lead sheathtechnique since it provides a convenient and easy-to-remove expedientfor compressing the elastomer during curing.

SUMMARY OF THE INVENTION The present invention provides a solution tothe above-described problem associated with curing elastomeric hosewhile encased in lead. The invention incorporates continuously windingthe lead covered hose about a drum positioned to rotate about a verticalaxis with the lead covered hose forming a coil over the drum and feedingcontinuously on and off the drum. The lead covered hose is heated to andmaintained at vulcanizing temperature while it is rotating on the drum,such that any given portion of the hose is cured between the time itenters the drum and leaves the drum. The lead casing is continuouslystripped from the cured hose as it leaves the drum. The position of thecoil on the drum remains substantially constant thereby permittingcontinuous uninterrupted curing of the hose. Moreover, since the lead isstripped from the house continuously as it exits from the drum, it istherefore no longer necessary to handle or transport heavy lengths oflead covered hose from one station to another during or after thevulcanizing operation and the lead is immediately available for reuse.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation view in asomewhat schematic form of the initial portion of the curing line andshows the hose exiting from the lead extruder and feeding continuouslyonto and exiting from the rotating drum.

FIG. 2 shows the terminal stage of the curing line, showing the hose asit exits from the drum and is fed through a lead stripper and onto areel;

FIGS. 1 and 2 when joined on the line 1-2 of each become a single viewof the entire curing line.

DETAILED DESCRIPTION Referring first to FIG. 1, the reel or spool 10 isrotatably mounted between a pair of stanchions 11, the spool 10 havingwound thereon a desired length of elastomeric hose 12 containing amandrel 13 continuously through the bore thereof. In the presentlypreferred practice of the invention, the uncured elastomeric hose 12 hasa nylon mandrel inserted in the bore; however, other materials may beused for the mandrel, as, for example, vulcanized rubber. The hose withthe mandrel therein is fed continuously off the reel 10 and into a leadextruder 14 which is supplied continuously with molten lead from a pot16 through a heated feed tube 17 and is powered by a motor and geardrive M. The lead is fed continuously from a head lead pot 16. In thepresently preferred practice of the invention, a vertical casing 18serves as a stanchion for the lead extruder 14 with the heated feed pipe17 positioned at a level below the extruder.

Uncured lead covered hose is thus formed, denoted by the general term 20in FIG. 1 and exits continuously from the extruder and then passes overa lay-up feeder pulley 30. A supporting frame 32 is provided with avertically disposed slot 31 formed therein with the pulley 30 mounted soas to transverse vertically in the slot 31. If desired, the feederpulley 30 may be supported vertically by a separate spring means (notillustrated) along the slot 31 to balance and support the weight of thelead covered hose traveling thereover. From the pulley 30, the leadcovered hose 20 travels continuously onto a drum 40 disposed so as torotate about a vertical axis, the drum being mounted on a turntable 41powered by a motor and gear drive 42. The lead covered hose 20 isinitially coiled about the drum beginning at the bottom and adding adesired number of revolutions and thereafter feeding onto the drum at alevel above that at which it exits. The drum is enclosed in an oven 43which has a vertical slot 43a formed in the wall thereof with the hosepassing through the slot as it enters the oven, the hose being free totravel vertically in the slot as it feeds over the lay-up feeder pulley30. As the drum is rotated, the hose feeds continuously off the lowerportion of the drum at the surface of the turntable 41 and exits throughan aperture 43b provided in the wall of the oven and located at stationB in FIG. 1. A flap seal S having a central slit therein is providedalong aperture 43b for preventing heat loss from the oven chamber 43.Furthermore, the motor and gear drive 42, although illustrated aslocated within the oven 43, may for convenience be external of the oven.

In the presently preferred practice of the invention, combustion productgases from a gas fired heater (not illustrated) are circulatedcontinuously through the oven by separate blower means (not illustrated)to provide the necessary heat for raising the lead covered hose to theproper vulcanizing temperature. However, it will be understood thatother techniques for heating may be employed as, for example,irradiating the lead covered hose as it rotates on the drum with heatlamps or other radiant heating devices or, alternatively, introducingsteam under pressure into a central chamber formed in the drum andthereby raising the drum to vulcanizing temperature. Furthermore, anydesired combination of these heating techniques may be used.

In the present practice of the invention, the motor gear drive 42 whichrotates drum 40 is synchronized with the speed of the extruder such thatsubstantially no tension is maintained in the lead encased hose as ittravels between the extruder 14 and the lay-up feeder pulley 30. It willbe understood that by appropriate selection of drum diameter and drumrotation speed, which is usually limited by the extruder output,complete curing of the hose on the drum at the rate at which it exitsfrom the extruder may be obtained by proper choice of the number ofcoils of hose wound on the drum. For example, in the present practice ofthe invention, the drum 40 has a diameter of 16 feet, with acorresponding circumference of approximately 50 feet, and the leadcovered hose 20 is wound 60 revolutions about the drum so that lrevolution per minute of the drum yields an output of 50 feet ofvulcanized hose per minute. This will be understood by observing that agiven portion of hose 50 feet in length entering the drum as the initialcoil, makes one revolution of the drum in 1 minute, and requires 60revolutions of the drum to exit from the drum at the terminal coil, thusremaining on the drum for 60 minutes. Thus, a portion of hose 50 feet inlength as a dwell period of 60 minutes on the drum, during which time itis maintained at vulcanizing temperature and is cured. Although the drumhas a diameter of 16 feet and rotates at a speed of l revolution perminute in the presently preferred practice, it will be understood thatthe diameter of the drum and the speed of rotation and the number ofcoils wrapped around the drum may be chosen for convenience inaccordance with the desired production rate consistent with themass-extrusion capability of lead extruder 14. The extruder 14, in thepresent practice of the invention, operates at a capacity of 120 poundsof lead per minute. The rate of extrusion may be varied to providesufficiently rapid lead encasement of the hose depending upon thediameter of the hose to be cured, in order to prevent any substantialtension between the extruder and the drum rotating at l revolution perminute.

Referring again to FIG. 1, the lead covered hose 20 is shown in solidoutline as it enters the drum during continuous curing. However, forinitial start-up of the curing operation, with no windings on the drum,the output of the extruder is fed initially onto the lower portions ofthe drum at the deck of the turntable with the initial position of thehose 20 and lay-up follower 30 shown in phantom outline in FIG. 1. Thedrum is then rotated until the desired number of coils are wound aboutthe drum whereupon the lay-up feeder pulley 30 is in the upper positionshown in solid outline and the hose is entering the drum at the top asillustrated in FIG. 1 in solid outline. When the desired number of coilshave been wound initially around the drum, the end of the hose is priedloose from the bottom of the coils at the deck of the turntable 41, andthe drum rotated such that the end of the lead covered hose is fedthrough aperture 43b to exit from the oven. Thereafter, as the drumrotates, the hose feeds continuously from the extruder, over the lay-upfeeder pulley 30 and onto the upper portion of the drum and exitscontinuously from the bottom of the drum at the turntable 41.

Referring now to FIG. 2, at station 1-2, the hose, after exiting fromthe drum passes through a tension puller 44. From the tension puller 44the cured lead covered hose 20a is fed continuously through a leadstripper 45 whereupon the lead casing is removed. The stripped curedhose H then feeds continuously onto a take-up reel 46 mounted between apair of stanchions 47 and driven by a motor gear drive 48. The tensionpuller 44 preferably comprises a pair of traction belts 4950 runninglongitudinally of the hose and contacting the hose on opposite sidesthereof. The traction belts 49 and 50 each orbit over a pair of rollers51 and 52 respectively which rollers are disposed transversely of thelead covered hose with one roller of each pair being driven to rotate inopposite directions by a motor gear drive 53 connected to the rollers bychain 54. Thus, as the cured lead covered hose emerges from the oven,the lead casing is stripped continuously therefrom and the cured hose His wound onto a spool for shipping. If desirable, forced cooling may beprovided on the lead covered hose as it emerges from the oven, forexample, by a water spray (not illustrated) or other cooling devices.Furthermore, as the lead casing is stripped from the cured hose by thestripper 44, the lead may be recycled by collecting the chips in ahopper (not shown) and feeding the chips into a conveyor belt (notshown) for returning them to the lead pot 16 for remelting, therebyminimizing the amount of lead required to maintain continuous operation.

The tension puller 44 maintains sufficient tension on the cured leadcovered hose to pull it off of the rotating drum 40 from the terminalcoil resting on the deck of turntable 41. It will be noted that atension puller is required in view of the weight of the coils of leadcovered hose resting on the terminal coil. Thus, in operation, the leadcovered hose feeds onto the drum near the top of the drum and is pulledfrom the drum at the bottom thereof by tension puller 44 while theterminal coil of the hose rests against the deck of turntable 41. Aseach coil exits continuously from the drum, the remaining coils slidevertically downward continuously such that the terminal coil isconstantly in contact with the deck of turntable 41.

When a desired amount of cured hose has been wound on the reel 46, it iscut. A portion of the reel (not illustrated) is then collapsedinternally and a source of water under pressure connected to the cut endof the cured hose. As the water under pressure is applied internally tothe hose, the mandrel 13 is discharged from the cured hose while same isstill on reel 46. After removal of the mandrel, the finished hose isremoved from the reel for inspection and shipment.

The method of the present invention thus enables elastomeric hose to bevulcanized continuously while encased in a lead sheath and the leadsheath stripped continuously from the cured hose. The present methodthus eliminates the necessity of transporting lengths of lead coveredhose to different stations during and after vulcanization.

Modifications and adaptations of the invention will be apparent to thosehaving ordinary skill in the art and the invention is limited only bythe spirit and scope of the following claims.

I claim:

1. An apparatus for vulcanizing elastomeric hose comprising:

a. means for axially moving a length of said hose;

b. means providing said hose with a lead covering as it is axiallymoved;

0. means to cause said covered hose to move in a helical path about avertical axis such that the hose enters said helical path at a verticalposition above the position at which it leaves said helical path;

d. means to heat said hose to a curing temperature while moving in saidhelical path;

e. means to remove said lead covering from the hose after passage fromsaid helical path.

f. said means to move said hose includes an enclosure having aperturesthrough which said hose is passed to and from and means within saidenclosure to maintain said hose in an annular path while there.

2. An apparatus as defined in claim 1, wherein said means for moving thehose in a helical path comprises an enclosure, a rotatable drum withinthe said enclosure, and the said enclosure has apertures adjacent theopposite ends of said drum through which apertures the hose is passed toand from a helical coiled condition about said drum.

3. An apparatus as defined in claim 2, wherein said drum is disposedwith its axis vertically and said inlet aperture for introduction of thehose into said enclosure is adjacent the upper portion of the latter andthe said aperture for exit of the hose from the enclosure is adjacentthe lower end thereof.

4. An apparatus as defined in claim 2, wherein means are provided forcirculating heated fluid to and from said enclosure.

1. An apparatus for vulcanizing elastomeric hose comprising: a. means for axially moving a length of said hose; b. means providing said hose with a lead covering as it is axially moved; c. means to cause said covered hose to move in a helical path about a vertical axis such that the hose enters said helical path at a vertical position above the position at which it leaves said helical path; d. means to heat said hose to a curing temperature while moving in said helical path; e. means to remove said lead covering from the hose after passage from said helical path. f. said means to move said hose includes an enclosure having apertures through which said hose is passed to and from and means within said enclosure to maintain said hose in an annular path while there.
 2. An apparatus as defiNed in claim 1, wherein said means for moving the hose in a helical path comprises an enclosure, a rotatable drum within the said enclosure, and the said enclosure has apertures adjacent the opposite ends of said drum through which apertures the hose is passed to and from a helical coiled condition about said drum.
 3. An apparatus as defined in claim 2, wherein said drum is disposed with its axis vertically and said inlet aperture for introduction of the hose into said enclosure is adjacent the upper portion of the latter and the said aperture for exit of the hose from the enclosure is adjacent the lower end thereof.
 4. An apparatus as defined in claim 2, wherein means are provided for circulating heated fluid to and from said enclosure. 